3300 janitors rally in Chicago; another planned for Schaumburg. More than 3300 janitors marched and rallied in downtown Chicago Sunday to kick off their contract negotiations with local cleaning contractors, building owners and office. …
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Helium is a Hellion to Hold! Barrage Balloons are made of sturdy cotton fabric coated with a rubber-like material which will hold helium - and this thin, buoyant gas is a Houdini for getting out of tight places. Natural rubber won't do - helium seeps through its "pores." A dense, non-porous, synthetic rubber was found ... But it wouldn't dissolve in an ordinary rubber solvent. How to apply it? Shell scientists came out of their laboratories with toluene. They had first produced toluene from petroleum to increase this country's production of TNT. And here was another use - it would dissolve the synthetic rubber so this could be spread over the fabric of the barrage balloon, making a helium-tight container. As toluene is precious for explosives, the scientists weren't quite satisfied - yet. More experimenting, and they had a solvent of toluene and another material that is plentiful and low in cost. Manufacturers of barrage balloons today are working with Shell-suggested formulas, and Shell scientists are continuing their research to conserve toluene. Barrage balloons, buoyed by helium or hydrogen, are mounting skyward on their vital mission. ..... 1942 Shell Oil Company Ad, A5477. 19420608
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